Dry cleaning establishments have become extremely commonplace throughout most of the industrialized nations of the world and have, for many years, provided valuable services in cleaning, sanitizing and restoring the usefulness of many fabrics and clothing garments which are not suitable for laundering operations. While the specific structures used in such dry cleaning operations vary somewhat with design, generally all utilize a closed drum having a rotatable tumbling basket disposed therein for receiving a quantity of clothing articles or the like for dry cleaning. The drum is equipped with an access door which is closed and preferably sealed during cleaning operations. The basic cleaning cycle involves the introduction of cleaning solvent into the drum and basket which is circulated through various filters as the tumbling basket is agitated or rotated to tumble the clothing articles through the solvent. At some point, usually under the control of a master timer, the solvent is extracted in a cycle which culminates in a high speed spin operation. Thereafter, a drying cycle is carried forward in which heated air is circulated through the basket and clothing articles. Often, the heated air used in drying is repeatedly heated prior to passing through the clothing articles and cooled thereafter to condense solvent out of the air and then reheated prior to the next circulation through the drying clothing articles. Once the drying cycle is complete, a reduction or cool down cycle is carried forward afterwhich the dry cleaning operation is complete.
When originally employed, such dry cleaning operations were relatively free of environmental concerns and regulations. Thus, in many early dry cleaning machines, the circulated air was simply vented to the atmosphere to carry away the solvent during the drying operation. However, recent environmental laws and regulations have imposed very strict constraints upon dry cleaning operations. In general, these regulations and laws have mandated the use of closed systems which do not vent solvent into the atmosphere generally. In addition, the environmental laws and regulations have essentially made necessary more efficient solvent recovery throughout the entire dry cleaning operation. The objective in addition to concerns over directly vented air into the atmosphere has also focused upon minimizing the solvent vapor vented between operations during unloading and loading as well as minimizing the amount of solvent residual remaining in clothes articles at the completion of the dry cleaning cycle. Many of the regulations and laws recently enacted have the stated purpose of reducing the solvent contaminants in the environment to avoid damage to the health and well being of laborers operating such machines. These regulations have an additionally stringent aspect to them in that the dry cleaning establishment environment often includes multiple dry cleaning machines as well as substantial quantities of recently cycled clothing articles awaiting pickup and removal. Thus, measurements directed to the total solvent content within the air at the cleaning facility essentially monitor the cumulative effect of many solvent sources.
While present available dry cleaning systems if properly operated may, in most instances, meet the present environmental and workplace safety regulations, they do so only if properly maintained and operated and optimally constructed. In view of the clear trend of environmental laws and regulations as well as workplace safety laws toward evermore strict and demanding requirements, it appears to be clear that present day dry cleaning systems will not be capable of meeting such stricter laws and regulations. Thus, there remains a continuing need in the art for evermore environmentally acceptable and safe to operate dry cleaning systems.